Audio: DRC: Change DRC to use lookup table based sine function

This change saves about 13 MPCS while the .bss RAM usage increases by 2 kB. TODO: A 16 bit sine function should cope with smaller lookup and be friendlier for cache. Signed-off-by: Seppo Ingalsuo <[email protected]>
thesofproject · Nov 17, 2023 · 8bc42e4 · 8bc42e4
1 parent e4de096
commit 8bc42e4
Show file tree

Hide file tree

Showing 2 changed files with 4 additions and 6 deletions.
diff --git a/src/audio/Kconfig b/src/audio/Kconfig
@@ -276,6 +276,7 @@ config COMP_CROSSOVER
 
 config COMP_DRC
 	bool "Dynamic Range Compressor component"
+	select LUT_TRIG_FIXED
 	select CORDIC_FIXED
 	select NUMBERS_NORM
 	select MATH_DECIBELS

diff --git a/src/include/sof/audio/drc/drc_math.h b/src/include/sof/audio/drc/drc_math.h
@@ -12,6 +12,7 @@
 #include <sof/audio/drc/drc_plat_conf.h>
 #include <sof/audio/format.h>
 #include <sof/math/numbers.h>
+#include <sof/math/lut_trig.h>
 #include <sof/math/trig.h>
 
 /* Unmark this define to use cordic arc sine implementation. */
@@ -59,9 +60,7 @@ static inline int32_t drc_sin_fixed(int32_t x)
 {
 	const int32_t lshift = drc_get_lshift(30, 30, 28);
 	int32_t denorm_x = drc_mult_lshift(x, PI_OVER_TWO_Q30, lshift);
-	int32_t sin_val = sin_fixed_16b(denorm_x);
-
-	return sin_val << 16;
+	return sofm_lut_sin_fixed_32b(denorm_x);
 }
 
 #ifdef DRC_USE_CORDIC_ASIN
@@ -87,9 +86,7 @@ static inline int32_t drc_asin_fixed(int32_t x)
 static inline int32_t drc_sin_fixed(int32_t x)
 {
 	const int32_t PI_OVER_TWO = Q_CONVERT_FLOAT(1.57079632679489661923, 30);
-	int32_t sin_val = sin_fixed_16b(Q_MULTSR_32X32((int64_t)x, PI_OVER_TWO, 30, 30, 28));
-
-	return sin_val << 16;
+	return sofm_lut_sin_fixed_32b(Q_MULTSR_32X32((int64_t)x, PI_OVER_TWO, 30, 30, 28));
 }
 
 #ifdef DRC_USE_CORDIC_ASIN